Custom foot orthoses for chronic metatarsalgia: study protocol for a participant- and assessor-blinded superiority randomized controlled trial

Background Chronic metatarsalgia (CM) causes significant pain and disability, affecting quality of life. Foot orthoses (FOs) including medially wedged designs with a metatarsal pad decrease excessive plantar pressure under the metatarsal heads, which is a known risk factor for developing CM. This FOs model may be effective in diminishing pain and improving function in these individuals. Thus, the objective of this trial is to compare the effects of medially wedged FOs with a metatarsal pad and sham FOs on pain and foot function in individuals with CM. Methods/design: This participant- and assessor-blinded superiority randomized controlled trial (RCT) with two parallel groups will be conducted in Trois-Rivières, Canada. Seventy-two participants with CM will be recruited from the Université du Québec à Trois-Rivières outpatient podiatry clinic and via social media invitations. They will be randomized into intervention (customized FOs) or control (sham FOs) groups and will be evaluated at baseline and after 6 and 12 weeks. The primary outcomes will be: (1) “pain” subscale of the Foot Function Index and (2) mean pain during walking for the most painful foot during the past week. The secondary outcomes will be: (1) Global rating of change, (2) the 5-level EQ-5D and (3) Foot Function Index (other subscales). Discussion The medially wedged FOs with a metatarsal pad are expected to provide a greater reduction in pain and improvement in foot function compared to the sham FOs. This trial will help guide FOs prescription recommendations for managing foot pain in individuals with CM in the future. Registry: Clinical Trial , NCT06962475, May 7, 2025, https://clinicaltrials.gov/study/NCT06962475